1
|
Jing SX, McDermott CM, Flanders PL, Reis-Havlat M, Chen SN, Bedran-Russo AK, McAlpine JB, Ambrose EA, Pauli GF. Chemical Transformation of B- to A-type Proanthocyanidins and 3D Structural Implications. JOURNAL OF NATURAL PRODUCTS 2024; 87:1416-1425. [PMID: 38687902 DOI: 10.1021/acs.jnatprod.4c00231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
In nature, proanthocyanidins (PACs) with A-type linkages are relatively rare, likely due to biosynthetic constraints in the formation of additional ether bonds to be introduced into the more common B-type precursors. However, A-type linkages confer greater structural rigidity on PACs than do B-type linkages. Prior investigations into the structure-activity relationships (SAR) describing how plant-derived PACs with B- and complex AB-type linkages affect their capacity for dentin biomodification indicate that a higher ratio of double linkages leads to a greater interaction with dentin type I collagen. Thus, A-type PACs emerge as particularly intriguing candidates for interventional functional biomaterials. This study employed a free-radical-mediated oxidation using DPPH to transform trimeric and tetrameric B-type PACs, 2 and 4, respectively, into their exclusively A-type linked analogues, 3 and 5, respectively. The structures and absolute configurations of the semisynthetic products, including the new all-A-type tetramer 5, were determined by comprehensive spectroscopic analysis. Additionally, molecular modeling investigated the conformational characteristics of all trimers and tetramers, 1-5. Our findings suggest that the specific interflavan linkages significantly impact the flexibility and low-energy conformations of the connected monomeric units, which conversely can affect the bioactive conformations relevant for dentin biomodification.
Collapse
Affiliation(s)
| | - Connor M McDermott
- Department of Chemistry, Grandview University, Des Moines, Iowa 50316, United States
| | | | | | | | | | | | | | | |
Collapse
|
2
|
Jing SX, Ferreira D, Pandey P, Klein LL, Chittiboyina AG, McAlpine JB, Lankin DC, Alania Y, Reis-Havlat M, Bedran-Russo AK, Chen SN, Pauli GF. Unprecedented Benzoquinone Motifs Reveal Post-Oligomerizational Modification of Proanthocyanidins. J Org Chem 2023; 88:13490-13503. [PMID: 37748101 PMCID: PMC10921432 DOI: 10.1021/acs.joc.3c00950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/27/2023]
Abstract
Proanthocyanidins (PACs) are complex flavan-3-ol polymers with stunning chemical complexity due to oxygenation patterns, oxidative phenolic ring linkages, and intricate stereochemistry of their heterocycles and inter-flavan linkages. Being promising candidates for dental restorative biomaterials, trace analysis of dentin bioactive cinnamon PACs now yielded novel trimeric (1 and 2) and tetrameric (3) PACs with unprecedented o- and p-benzoquinone motifs (benzoquinonoid PACs). Challenges in structural characterization, especially their absolute configuration, prompted the development of a new synthetic-analytical approach involving comprehensive spectroscopy, including NMR with quantum mechanics-driven 1H iterative functionalized spin analysis (HifSA) plus experimental and computational electronic circular dichroism (ECD). Vital stereochemical information was garnered from synthesizing 4-(2,5-benzoquinone)flavan-3-ols and a truncated analogue of trimer 2 as ECD models. Discovery of the first natural benzoquinonoid PACs provides new evidence to the experimentally elusive PAC biosynthesis as their formation requires two oxidative post-oligomerizational modifications (POMs) that are distinct and occur downstream from both quinone-methide-driven oligomerization and A-type linkage formation. While Nature is known to achieve structural diversity of many major compound classes by POMs, this is the first indication of PACs also following this common theme.
Collapse
Affiliation(s)
- Shu-Xi Jing
- Pharmacognosy Institute, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
- Department of Pharmaceutical Science, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Daneel Ferreira
- Department of Biomolecular Sciences, The University of Mississippi, University, Mississippi 38677, USA
- National Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, USA
| | - Pankaj Pandey
- Department of Biomolecular Sciences, The University of Mississippi, University, Mississippi 38677, USA
- National Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, USA
| | - Larry L. Klein
- Institute for Tuberculosis Research, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
- Department of Pharmaceutical Science, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Amar Gopal Chittiboyina
- Department of Biomolecular Sciences, The University of Mississippi, University, Mississippi 38677, USA
- National Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, USA
| | - James B. McAlpine
- Pharmacognosy Institute, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
- Institute for Tuberculosis Research, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
- Department of Pharmaceutical Science, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - David C. Lankin
- Pharmacognosy Institute, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
- Department of Pharmaceutical Science, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Yvette Alania
- Department of General Dental Sciences, School of Dentistry, Marquette University, Milwaukee, Wisconsin 53233, USA
| | - Mariana Reis-Havlat
- Department of General Dental Sciences, School of Dentistry, Marquette University, Milwaukee, Wisconsin 53233, USA
| | - Ana K. Bedran-Russo
- Department of General Dental Sciences, School of Dentistry, Marquette University, Milwaukee, Wisconsin 53233, USA
| | - Shao-Nong Chen
- Pharmacognosy Institute, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
- Institute for Tuberculosis Research, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
- Department of Pharmaceutical Science, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Guido F. Pauli
- Pharmacognosy Institute, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
- Institute for Tuberculosis Research, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
- Department of Pharmaceutical Science, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
| |
Collapse
|
3
|
Hu Q, Yu W, Fan Y, Kuang J, Cheng Z. Silicon Doped Carbon Dots as an New Ratiometric Fluorescence Probe for Proanthocyanidins Assay Based on the Redox Reaction Between Cr(VI) and Proanthocyanidins. J Fluoresc 2023; 33:849-858. [PMID: 36595093 DOI: 10.1007/s10895-022-03131-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 12/15/2022] [Indexed: 01/04/2023]
Abstract
In the study, silicon doped carbon quantum dots (Si-CQDs) was prepared by one-pot hydrothermal method with (3-aminopropyl) triethoxysilane (APTES) and o-phenylenediamine (OPD) as raw materials. Then a new ratiometric fluorescent probe (RF-probe) was successfully established for sensitively and selectively monitoring proanthocyanidins (PAs) with a linear range of 10-500 nM and limit of detection (LOD) of 5.6 nM. that is, the fluorescence (FL) intensity of Si-CQDs at 570 nm was used as the built-in reference, while dopamine (DA) reacting with 4-hexylresorcinol (4-HR) could produce a new fluorescent substance (named as azamonardine, AZMON), and its FL intensity at 480 nm was reduced because Cr(VI) could oxidize DA to generate quinone without fluorescence. In the presence of PAs, Cr(VI) was reduced to Cr(III), which caused that the amount of DA reacting with 4-HR was increased, thus the FL intensity of AZMON was recovered. Furthermore, the RF-probe was successfully used for the determination of PAs in black goji berry from two different areas and PAs capsule with satisfactory results compared to the standard HPLC method.
Collapse
Affiliation(s)
- Qingqing Hu
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, China West Normal University, Nanchong, 637002, China
| | - Weihua Yu
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, China West Normal University, Nanchong, 637002, China
| | - Yucong Fan
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, China West Normal University, Nanchong, 637002, China
| | - Jianhua Kuang
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, China West Normal University, Nanchong, 637002, China
| | - Zhengjun Cheng
- Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, China West Normal University, Nanchong, 637002, China.
- Institute of Applied Chemistry, China West Normal University, Nanchong, 637002, China.
| |
Collapse
|
4
|
Zhou B, Alania Y, Reis M, Jing SX, McAlpine JB, Bedran-Russo AK, Chen SN, Ferreira D, Pauli GF. Seco B-Type Oligomers from Pinus massoniana Expand the Procyanidin Chemical Space and Exhibit Dental Bioactivity. JOURNAL OF NATURAL PRODUCTS 2022; 85:2753-2768. [PMID: 36382951 PMCID: PMC9789173 DOI: 10.1021/acs.jnatprod.2c00664] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Investigation of a pine bark extract for bioactive proanthocyanidin oligomers resulted in the isolation of structurally related dimeric seco B-type procyanidin derivatives, 1-5. This includes scalemic mixtures of gambiriin A1 (1a) and A2 (2a) and their newly described optical antipodes, ent-gambiriin A1 (1b) and ent-gambiriin A2 (2b), respectively, as well as a racemic mixture of the newly described (ent-)gambiriin A5 (3a/3b). Furthermore, the study now fully characterizes the previously reported optically pure dimers gambiriin B1 (4) and gambirflavan D1 (5), and characterized the novel seco B-type procyanidin trimer, 6 (gambirifuran C1). Thermal conversion of catechin in aqueous solution provided further evidence for the structures of 1-6 and led to the purification of semisynthetic 1a and 2a as well as additional dimers 7-10. Elucidating the structures of the natural dimers, 1-5, from comprehensive NMR and ECD data and synthetic evidence provided crucial reference points for establishing the structure of the seco B-type procyanidin trimer, 6. Serving as assigned building blocks, data from the dimers supported the 3D structural assignment of 6 based on NMR substituent chemical shift differences (s.c.s., syn. ΔδC) and component-based empirical ECD calculations. Within the newly characterized series of PAC-related molecules, 5 exhibited high dentin biomodification potential. In addition, considering the nomenclature issues and plausible biosynthetic pathways of this group of compounds led to a consolidated nomenclature of all currently known seco B-type procyanidins. These findings, thereby, expand the chemical space of bioactive catechin oligomers, which have promise as agents for the natural enhancement of dental biomaterials. Finally, the current knowledge of the chemical space of seco B-type procyanidin derivatives was compiled to the level of absolute configuration.
Collapse
Affiliation(s)
- Bin Zhou
- Pharmacognosy Institute and Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, USA
| | - Yvette Alania
- Department of Restorative Dentistry, College of Dentistry, University of Illinois at Chicago, Chicago, Illinois 60612, USA
| | - Mariana Reis
- Department of Restorative Dentistry, College of Dentistry, University of Illinois at Chicago, Chicago, Illinois 60612, USA
| | - Shu-Xi Jing
- Pharmacognosy Institute and Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, USA
| | - James B. McAlpine
- Pharmacognosy Institute and Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, USA
| | - Ana K. Bedran-Russo
- Department of Restorative Dentistry, College of Dentistry, University of Illinois at Chicago, Chicago, Illinois 60612, USA
| | - Shao-Nong Chen
- Pharmacognosy Institute and Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, USA
| | - Daneel Ferreira
- National Center for Natural Products Research and Department of Biomolecular Sciences, Division of Pharmacognosy, School of Pharmacy, University of Mississippi, University, Mississippi 38677, USA
| | - Guido F. Pauli
- Pharmacognosy Institute and Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, USA
| |
Collapse
|
5
|
Jing SX, Reis M, Alania Y, McAlpine JB, Chen SN, Bedran-Russo AK, Pauli GF. B-type Proanthocyanidins with Dentin Biomodification Activity from Cocoa ( Theobroma cacao). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:12456-12468. [PMID: 36134876 PMCID: PMC9547875 DOI: 10.1021/acs.jafc.2c04288] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
To enable translational studies, a scalable preparative isolation scheme was developed for underivatized cocoa (Theobroma cacao) proanthocyanidins (PACs), affording six all-B-type oligomeric PACs, including a new tetramer 4. Their structures, including absolute configuration, were unambiguously established by comprehensive spectroscopic and chemical methods. Evaluation of the PACs' dentin biomodification properties employed dynamic mechanical and infrared spectroscopic analyses in dentin bioassay models. PAC treatment enhanced the biomechanical strength of dentin by 5- to 15-fold compared to untreated dentin. Among the PAC agents, the pentamer, cinnamtannin A3 (6), led to the highest complex modulus value of 131 MPa, whereas the "branched" tetramer, 4, showed the lowest, yet still significant bioactivity. This study of specifically singly linked medium-length oligomeric PACs indicates that the linkage site is paramount in determining the potency of these PACs as dentin biomodifiers.
Collapse
Affiliation(s)
- Shu-Xi Jing
- Pharmacognosy Institute and Department of Pharmaceutical
Science, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612,
USA
| | - Mariana Reis
- Department of General Dental Sciences, School of Dentistry,
Marquette University, Milwaukee, WI 53233, USA
| | - Yvette Alania
- Department of General Dental Sciences, School of Dentistry,
Marquette University, Milwaukee, WI 53233, USA
| | - James B. McAlpine
- Pharmacognosy Institute and Department of Pharmaceutical
Science, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612,
USA
| | - Shao-Nong Chen
- Pharmacognosy Institute and Department of Pharmaceutical
Science, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612,
USA
| | - Ana K. Bedran-Russo
- Department of General Dental Sciences, School of Dentistry,
Marquette University, Milwaukee, WI 53233, USA
| | - Guido F. Pauli
- Pharmacognosy Institute and Department of Pharmaceutical
Science, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612,
USA
| |
Collapse
|
6
|
Betkekar VV, Suzuki K, Ohmori K. Total Synthesis of Parameritannin A2, a Branched Epicatechin Tetramer with Two Double Linkages. Angew Chem Int Ed Engl 2022; 61:e202205106. [PMID: 35534438 PMCID: PMC9401032 DOI: 10.1002/anie.202205106] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Indexed: 11/06/2022]
Abstract
The first total synthesis of parameritannin A2 (1), a branched epicatechin (EC) tetramer is reported. The "phloroglucinol trick" was used to circumvent two synthetic issues encountered when assembling four EC units, namely, the steric constraint and the formation of the C4-C6 interflavan linkage. As a substructure of the middle EC unit, phloroglucinol enabled the single-step assembly of two EC units (top and side) through A-type linkages. The middle EC unit was constructed by conducting a newly developed three-carbon flavan annulation via a Pummerer/Friedel-Crafts cascade reaction to furnish a trimeric intermediate bearing a thio-leaving group at C4 position, which allowed the final installation of the bottom EC unit.
Collapse
Affiliation(s)
- Vipul V. Betkekar
- Department of ChemistryTokyo Institute of Technology2-12-1, O-okayamaMeguro-ku, Tokyo152-8551Japan
| | - Keisuke Suzuki
- Department of ChemistryTokyo Institute of Technology2-12-1, O-okayamaMeguro-ku, Tokyo152-8551Japan
| | - Ken Ohmori
- Department of ChemistryTokyo Institute of Technology2-12-1, O-okayamaMeguro-ku, Tokyo152-8551Japan
| |
Collapse
|
7
|
Betkekar VV, Suzuki K, Ohmori K. Total Synthesis of Parameritannin A2, a Branched Epicatechin Tetramer with Two Double Linkages. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202205106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Vipul V. Betkekar
- Department of Chemistry Tokyo Institute of Technology 2-12-1, O-okayama Meguro-ku, Tokyo 152-8551 Japan
| | - Keisuke Suzuki
- Department of Chemistry Tokyo Institute of Technology 2-12-1, O-okayama Meguro-ku, Tokyo 152-8551 Japan
| | - Ken Ohmori
- Department of Chemistry Tokyo Institute of Technology 2-12-1, O-okayama Meguro-ku, Tokyo 152-8551 Japan
| |
Collapse
|
8
|
Jing SX, Alania Y, Reis M, McAlpine JB, Chen SN, Bedran-Russo AK, Pauli GF. Proanthocyanidin Tetramers and Pentamers from Cinnamomum verum Bark and Their Dentin Biomodification Bioactivities. JOURNAL OF NATURAL PRODUCTS 2022; 85:391-404. [PMID: 35107279 PMCID: PMC8881394 DOI: 10.1021/acs.jnatprod.1c00972] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
To enable the further exploration of structure-activity relationships (SARs) of proanthocyanidins (PACs) with dentin biomodification abilities, Cinnamomum verum was selected for scaled-up purification of mixed A-/B-type, medium-size PAC oligomers. Sequential purification by centrifugal partition chromatography (CPC), Sephadex LH-20, and semiprep HPLC chromatography yielded four underivatized tetrameric (5-8) and two pentameric (9-10) PACs. Their unambiguous structural characterization involved extensive spectral and chemical degradation approaches to show that epicatechin units are connected by plant-specific combinations of doubly linked A- and singly linked B-type interflavanyl bonds. The biomechanical properties (via dynamic mechanical analysis) and physicochemical structure (via infrared spectroscopy) were assessed to evaluate the biomodification potency of PAC-treated collagen in a preclinical dentin model. This study revealed that (4→8) versus (4→6) bonds in PAC interflavan linkages have limited influence on biomechanical outcomes of dentin. By exhibiting a 25-fold increase in the complex modulus of treated dentin compared to control, aesculitannin E (5) was found to be the most potent PAC known to date for enhancing the mechanical properties of dentin in this preclinical model.
Collapse
Affiliation(s)
- Shu-Xi Jing
- Pharmacognosy Institute and Department of Pharmaceutical Science, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Yvette Alania
- Department of General Dental Sciences, School of Dentistry, Marquette University, Milwaukee, WI 53233, USA
| | - Mariana Reis
- Department of General Dental Sciences, School of Dentistry, Marquette University, Milwaukee, WI 53233, USA
| | - James B. McAlpine
- Pharmacognosy Institute and Department of Pharmaceutical Science, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Shao-Nong Chen
- Pharmacognosy Institute and Department of Pharmaceutical Science, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Ana K. Bedran-Russo
- Department of General Dental Sciences, School of Dentistry, Marquette University, Milwaukee, WI 53233, USA
| | - Guido F. Pauli
- Pharmacognosy Institute and Department of Pharmaceutical Science, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA
| |
Collapse
|
9
|
Reis M, Zhou B, Alania Y, Leme-Kraus AA, Jing S, McAlpine JB, Chen SN, Pauli GF, Bedran-Russo AK. Unveiling structure-activity relationships of proanthocyanidins with dentin collagen. Dent Mater 2021; 37:1633-1644. [PMID: 34563363 PMCID: PMC8791559 DOI: 10.1016/j.dental.2021.08.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 08/16/2021] [Accepted: 08/17/2021] [Indexed: 10/20/2022]
Abstract
OBJECTIVE To elucidate the structure-activity relationships (SARs) of proanthocyanidins (PACs) with type I collagen using sixteen chemically defined PACs with degree of polymerization (DP) 2-6. METHODS Under a dentin model, the biomimicry of PACs with type I collagen was investigated by dynamic mechanical analysis (DMA) and infrared spectroscopy. The dentin matrix was modified with PACs from Pinus massoniana [monomers (Mon-1 and Mon-2), dimers (Dim-1-Dim-4), trimers (Tri-1-Tri-4), tetramers (Tet-1-Tet-5), and hexamer (Hex-1)]. A strain sweep method in a 3-point bending submersion clamp was used to assess the viscoelastic properties [storage (E'), loss (E"), and complex moduli (E*) and tan δ] of the dentin matrix before and after biomodification. Biochemical analysis of the dentin matrix was assessed with FTIR spectroscopy. Data were statistically analyzed using one-way ANOVA and post-hoc tests (α = 0.05). RESULTS DP had a significant effect on modified dentin moduli (tetramers ≈ trimers > hexamers ≈ dimers > monomers ≈ control, p < 0.001). Trimers and tetramers yielded 6- to 8-fold increase in the mechanical properties of modified dentin and induced conformational changes to the secondary structure of collagen. Modifications to the tertiary structure of collagen was shown in all PAC modified-dentin matrices. SIGNIFICANCE Findings establish three key SARs: (i) increasing DP generally enhances biomimicry potential of PACs in modulating the mechanical and chemical properties of dentin (ii) the secondary structure of dentin collagen is affected by the position of B-type inter-flavanyl linkages (4β → 6 and 4β → 8); and (iii) the terminal monomeric flavan-3-ol unit plays a modulatory role in the viscoelasticity of dentin.
Collapse
Affiliation(s)
- Mariana Reis
- Department of General Dental Sciences, School of Dentistry, Marquette University, Milwaukee, WI, 53233, United States; Department of Restorative Dentistry, College of Dentistry, University of Illinois at Chicago, Chicago, IL, 60612, United States
| | - Bin Zhou
- Pharmacognosy Institute and Department of Pharmaceutical Sciences (PSCI), College of Pharmacy, University of Illinois at Chicago, Chicago, IL, 60612, United States
| | - Yvette Alania
- Department of General Dental Sciences, School of Dentistry, Marquette University, Milwaukee, WI, 53233, United States; Department of Restorative Dentistry, College of Dentistry, University of Illinois at Chicago, Chicago, IL, 60612, United States
| | - Ariene A Leme-Kraus
- Department of Restorative Dentistry, College of Dentistry, University of Illinois at Chicago, Chicago, IL, 60612, United States
| | - Shuxi Jing
- Pharmacognosy Institute and Department of Pharmaceutical Sciences (PSCI), College of Pharmacy, University of Illinois at Chicago, Chicago, IL, 60612, United States
| | - James B McAlpine
- Pharmacognosy Institute and Department of Pharmaceutical Sciences (PSCI), College of Pharmacy, University of Illinois at Chicago, Chicago, IL, 60612, United States
| | - Shao-Nong Chen
- Pharmacognosy Institute and Department of Pharmaceutical Sciences (PSCI), College of Pharmacy, University of Illinois at Chicago, Chicago, IL, 60612, United States
| | - Guido F Pauli
- Pharmacognosy Institute and Department of Pharmaceutical Sciences (PSCI), College of Pharmacy, University of Illinois at Chicago, Chicago, IL, 60612, United States
| | - Ana K Bedran-Russo
- Department of General Dental Sciences, School of Dentistry, Marquette University, Milwaukee, WI, 53233, United States; Department of Restorative Dentistry, College of Dentistry, University of Illinois at Chicago, Chicago, IL, 60612, United States.
| |
Collapse
|
10
|
Spray treatment of leaves with Fe2+ promotes procyanidin biosynthesis by upregulating the expression of the F3H and ANS genes in red rice grains (Oryza sativa L.). J Cereal Sci 2021. [DOI: 10.1016/j.jcs.2021.103231] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
11
|
Guedes D, Martins GR, Jaramillo LYA, Simas Bernardes Dias D, da Silva AJR, Lutterbach MTS, Reznik LY, Sérvulo EFC, Alviano CS, Alviano DS. Proanthocyanidins with Corrosion Inhibition Activity for AISI 1020 Carbon Steel under Neutral pH Conditions of Coconut ( Cocos nucifera L.) Husk Fibers. ACS OMEGA 2021; 6:6893-6901. [PMID: 33748603 PMCID: PMC7970558 DOI: 10.1021/acsomega.0c06104] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 02/18/2021] [Indexed: 05/24/2023]
Abstract
Cocos nucifera L. is a palm tree (Arecaceae) with a high economic value. The coconut husk fibers are nonedible, thick, and abrasion-resistant and correspond up to 85% of biomass discarded as solid waste residue. Therefore, the husk fibers are an underexploited byproduct with a high content of extractives of unreported nature. Two varieties of C. nucifera L. husk extracts were investigated to uncover bioactive metabolites and their possible application as a green corrosion inhibitor for carbon steel AISI 1020 under neutral pH conditions. The chemical analysis indicated 3% (w/w) of proanthocyanidins in the husk fibers with a high B-type procyanidin content. The husk fibers' crude extract showed promising results as an eco-friendly corrosion inhibitor for carbon steel AISI 1020 under neutral pH conditions. Although it formed a film on the metal surface in all tested concentrations (0.4, 0.8, 1.2, and 1.6 g L-1), the highest protective efficiency was shown at a concentration of 1.2 g L-1, determined by electrochemical techniques and mass loss. This was the first comprehensive report on coconut husk fibers' chemical composition, which was similar between the two varieties with potential for industrial application.
Collapse
Affiliation(s)
- Douglas Guedes
- Escola de Química, Universidade Federal do Rio de Janeiro, CT, Bloco E. Avenida Athos da Silveira Ramos, 149, Cidade Universitária, Rio de Janeiro 21941-909, RJ, Brazil
| | - Gabriel R Martins
- Instituto de Pesquisas de Produtos Naturais, Universidade Federal do Rio de Janeiro, CCS, Bloco H. Avenida Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro 21941-902, RJ, Brazil
| | - Lizeth Y A Jaramillo
- Escola de Química, Universidade Federal do Rio de Janeiro, CT, Bloco E. Avenida Athos da Silveira Ramos, 149, Cidade Universitária, Rio de Janeiro 21941-909, RJ, Brazil
| | - Diogo Simas Bernardes Dias
- Escola de Química, Universidade Federal do Rio de Janeiro, CT, Bloco E. Avenida Athos da Silveira Ramos, 149, Cidade Universitária, Rio de Janeiro 21941-909, RJ, Brazil
| | - Antonio Jorge R da Silva
- Instituto de Pesquisas de Produtos Naturais, Universidade Federal do Rio de Janeiro, CCS, Bloco H. Avenida Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro 21941-902, RJ, Brazil
| | - Marcia T S Lutterbach
- Divisão de Corrosão e Degradação, Instituto Nacional de Tecnologia, Avenida Venezuela, 82. Praça Mauá, Rio de Janeiro 20081-312, RJ, Brazil
| | - Leila Y Reznik
- Escola de Química, Universidade Federal do Rio de Janeiro, CT, Bloco E. Avenida Athos da Silveira Ramos, 149, Cidade Universitária, Rio de Janeiro 21941-909, RJ, Brazil
| | - Eliana F C Sérvulo
- Escola de Química, Universidade Federal do Rio de Janeiro, CT, Bloco E. Avenida Athos da Silveira Ramos, 149, Cidade Universitária, Rio de Janeiro 21941-909, RJ, Brazil
| | - Celuta S Alviano
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, CCS, Bloco I. Avenida Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro 21941-902, RJ, Brazil
| | - Daniela S Alviano
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, CCS, Bloco I. Avenida Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro 21941-902, RJ, Brazil
| |
Collapse
|